Background
Recently there has been some minor controversy regarding the use of milk thistle in women
with a history of breast cancer. Is there any validity to these concerns? Not really. It is just
confusing to the consumer. For example, the susan G. komen for the Cure® website
(ww5.komen.org/BreastCancer/Milkthistle.html) states the following: “theoretically, because milk
thistle plant extract might have estrogenic effects, women with hormone sensitive conditions should
avoid milk thistle above ground parts. . . the more commonly used milk thistle seed extracts are
not known to have estrogenic effects.”
The Problem with Fuzzy Logic
What is sad is that such cautions may keep women who really could benefit from taking a milk
thistle extract from doing so. yes, the common milk thistle extracts are made from the seed. so,
these cautions popping up on many websites as well as newsletters are really irrelevant. On the
flip side, the research is quite promising on using milk thistle extract as both a preventive
substance as well as a possible therapeutic aid in breast cancer patients. some of the
beneficial effects noted in the many scientific investigations of milk thistle extracts containing
silymarin and its major constituent, silibinin, include:
• Prevention of the expression of genes and enzymes pivotal in breast cancer development.
• Inhibition of breast cancer cell growth and the inhibition of key pathways that cancer cells
use to grow.
• Promotion of apoptosis (programmed cell death) in breast cancer cells.
New Data
Unregulated protein synthesis is a key event in the development of breast cancer. Regulation of
protein synthesis is required for cell growth, proliferation, differentiation and cellular
homeostasis. loss of this regulation leads to excessive cell growth in cancer cells, the greater
the loss the more aggressive the cancer. the primary regulator is messenger RNa (mRNa) which in
turn is influenced by translation initiation factors that lead to the expression of the code on
the mRNa. silibinin has been shown to block the signaling of these translation initiation factors
in a new and very novel manner. this is a very specific molecular mechanism of how silibinin can
inhibit growth
of cells that have been transformed into cancerous cells.
